Roof and waterproofing membranes and linings have long been used to protect buildings, to contain water in ponds and decorative water features, to prevent leaching of contaminants from landfills, and for other purposes. While these membranes have utility, leakage through the membranes is an ongoing problem. The efforts to contain and locate leakage have resulted in the rise of specialized consultants, air and vacuum testable membranes, and, in recent history, electrical testing methods that not only determine if a leak is present in a membrane system, but where the leak is located.
Such an electrical testing method and system that determines both that a leak is present in a membrane system, and where the leak is located is disclosed in the Inventor's U.S. Pat. No. 8,566,051, which is hereby incorporated by reference. This Application discloses a system for detecting and locating a leak through a membrane that includes a detector array and computer. The detector array includes a boundary wire loop, sensors, and leads. The boundary wire loop surrounds the area to be tested and generates electrical tension on the surface of the membrane. The sensors are laid out in a sensor array and are placed on top of a membrane and within the boundary wire loop. The sensors are encased in a plastic covered cable or individual wires which have open ends for their terminations forming a cable so that the sensors made by the open terminations form a chain. Each sensor communicates individually with the computer and the signals from the sensors are used by the computer to perform vector mapping that detects and locates leaks through the membrane.
Although successful for its purpose in many situations, it may be improved upon in situations where anything conductive is running across the roof or waterproofing, or is contained in the overburden layer, and that element is connected to ground. Examples of such situations include where the leak detection system is covered with soil overburden that has conduits on it, concrete overburden that is tied to the grounded structure of the building, or a combination thereof. More specific examples of such elements may include conduits or lightning cables. In such situations, the leak detection system may detect grounding from above and falsely identify it as leaks through the waterproofing membrane. If the element connected to ground is disconnected from the ground or electrically isolated, then the leak detection system will continue to work as envisioned. It is desirable, however, for the leak detection system to include a feature to address such situations, rather than dealing with the grounded elements on a case by case basis. Therefore there is a need for an improvement over the Inventor's prior invention that addresses such situations.